Phonograph and analogous apparatus



E. GRISSINGER.

PHONOGRAPH AND ANALOGOUS APPARATUS.

APPLICATION FILED JUNE 12, 1918- Patented May 11, 1920.

INVENTOR v BY f a {a flail/ATTORNEY UNITED STATES PATENT OFFICE.

ELWOOD GRISSINGER, OF BUFFALO, NEW YORK, .ASSIGNOR TO LUCY ASl-IGRISSINGER,

' OF BUFFALO, NEW YORK. I

PHONOGRAPH AND ANALOGOUS APPARATUS.

I Application filed June 12,

To all whom it may concern:

Be it known that I, ELwooD GRissiNcER, a citizen of the United States,and resident of Buffalo, in the county of Erie and State of New York,have invented certain new 'or other apparatus where rigid, frictionless,

noiseless pivoting is necessary or desirable in order to insurefaithful, undistorted mechanical receiving or transmission of highfrequency or complex wave energy.

In my 236,735, filed May 27th, 1918, I have disclosed a constructionwherein the effects of mechanical resonance are eliminated from thevibratory system, by making the lever arm rigid and pivoting it uponspaced piano steel wires stretched to the safe limit of their tensilestrength thereby insuring a-predetermined, rigidly fixed path ofmovement for all parts or particles of the lever.

My present invention relates more particularly to the use of the spaced;stretched wires and it involves in addition thereto, a means for furtherpredet'ermining and fixing the location of the pivotal axis of thelever. Broadly stated, the saidmeans consists of a third elementadaptedto apply a thrust perpendicularly to the plane of the wires, and along aline parallel with and midway between them. The means em-' ployed forthis purpose may be varied, but in this application I disclose how apair of alined steel balls may be used for such purpose.

By providing suitable adjusting screws, the pivotal means may be verypowerfully forced against the lever thus affording a convenient and veryeffective means for transversely displacing the wires and therebystretching them to any desired degree of tension. i

By the above expedient, the alined balls become the physical bearingsurfaces for the pivotal movement of the lever. These bearing surfacesare forced into contact with relatively enormous pressure by thesymmetrically applied stresses of the spaced Specification of LettersPatent.

prior application, Serial No.

Patented May 11, 1920.

1918. Serial Nb. 239,513.

wires. This prevents. all possibility of jumping or noise producingmovements at the point of contact of the lever with its bearing. Thebearing parts are preferably of very hard steel and are formed withsmooth, preferably polished surfaces.

My invention will be more fully understood from the following detaileddescription thereof in connection with .the accompanying drawings, in-which- I Figure 1 is a face view of a phonographic sound box. showingthe spaced stretched} wire suspension;

Fig. 2 is a section on the line 22, Fig.

1, the lever and pi'votal mounting being shown in side elevation;

Fig. 3 is an enlarged vertical section on the line33,Fig. 1;,

Fig. 1, is an elevation endwise of the lever; a

Fig. 5 is a detail view showing the pivotal mounting as in Fig. 4 but ona larger scale; and Fig. 6 is a detail section showing a modified formof adjustable ball support.

In these drawings, the sound box comprises the annular ring 1, formedwith the inwardly projecting annular flange2, and the back-plate 3,secured to ring 1 by screws 1. In the recess between flange 2 and plate3 is clamped the diaphragm 5 of mica or other suitable material,disposed between a pair of rubber cushioning rings 6 which Thelever arm11 may be attached to the diaphragm directly orthrough the screw andadjustable nuts shown in Fig. 2. The other end of the lever is providedwith a socket 12 and binding screw 13 for holding a needle forreproducing or a cuttin point for recording, as indicated at 14. Thislever is preferably of an aluminum alloy, and the long arm thereof maybe made light yet very rigid. The pivotal portion is relatively massivefor purposes of strength, and because a certain amount of weight nearthe pivotal axis is not so objectionable and is in some respectsadvantageous so far as concerns pure tone transmission.

The resilient members adapted to permit resilient pivotal movements ofthe lever while powerfully opposing movements in,

plates 21, 22, each secured preferably by a central bolt 23, passingdownward between the wires so that the clamping plates will bind equallyon both of the wires to be secured thereby.

As shown in the drawings, the wires are comparatively close togetherwhere they pass through the lever and are spread apart -to aconsiderably wider distance at their clamping points so that when highlytensioned, they have considerable effect in bracing or staying the leveragainst longitudinal movement and also against any skewing of itspivotal. axis.

Such spaced wires when very highly tensioned' afford a frictionless,noiseless mounting for pivotal movement of the lever about an axisparallel with and midway between the wires. According to my presentinvention, I use a physical means for determining the axis consisting ofa pair of alined balls 24, 24, applied against the lower side of thelever so as to have two alined points of contact therewith in a planemidway between the spaced wires. The balls 24 are preferably the veryhard, polished steel balls such as are commonly used for ball bearings.They may be thrust upward vertically against the lever as powerfully asmay be desired, by means of screws 26, 26.

The stress of the wires against the balls being in a direction endwiseof the screws, it is, of course, possible to use a single screw for eachball, and the ball may be located in a conicalrecess in-the end of thescrew as indicated --in Fig. 6. For some reasons,

however, it is preferable to use a s ecial adjustable mounting for theballs an a special bearing surface for the lever. As shown in Figs. 3, 4and5, the balls are supported on a bed late 27, which may be of hardenedsteel i desired. formed with V grooves 28 parallel with each other andparallel with the plane of movement of the lever arm.

"The plate 27 is slidably mounted on a centering stud 29, and fourscrews, 26, are shown for supporting the plate and for adj ustablyapplying the desired upward thrust against the lever arm.

The lever surface against which the balls bear, may be a separate steel'plate 30, secured to the lever arm by screws 31. The

bearing surface on the plate 30 may be provided with a transverse groove32. This groove may be of circular cross-section of considerably greaterradius of curvature than the balls. Being at right angles to the grooves28 in the bed plate 27, they together afford a convenient means forlocating and centering the balls so that they will be in a line exactlytransverse to the lever, will be spaced a fixed distance apart, andtheir line of thrust will be midway between the planes of downwardstress of the spaced wires 26.

The position of the wires 26 may be accurately fixed with reference tothe transverse groove 32 by forming clamping grooves therefor intheplate 30 and cooperating rooves in the bottom surface of the lever. Thelatter surface maybe a separate plate 33. Plate 30 preferably is andplate 33 may be of ,hardened steel, especially.

where the lever is made of aluminum oraluminum alloy for purposes oflightness. This is because under ordinary conditions of use, thevibration of the lever will cause the highly tensioned piano wires torapidly cut aluminum, aluminum alloys or even ordinary soft steel.

lVhere ordinary bearing balls are used, the surfaces bearing on thelever will of course be spherical and while this theoreti cally gives aslight rocking contact instead of a mathematically exact pivotalmovement about a single axis, nevertheless, for the very slightmovements involved in phonographic work, any rolling component in themovement will be very small. Even if the proportions of the parts aresuch as to give considerable rocking movement, this movement willnevertheless be rigidly and precisely predetermined, so that the pathsof movement of all points or particles of the lever arm will beinvariable even though not absolutely perfect arcs ofcircles perfectlyconcentric with a single axis. If the balls are no larger than of aninchin diameter the departure from the true circle movement will be small,and if the balls be only half as large, that is of an inch diameter, thedeparture will be only one-quarter as great and will be negligible.

The halls may be set with the bearing surfaces thereof at the desiredheight with reference to the clamping points of the wires by means ofthe set screws or they may be permanently fixed in such position, withthe wires strung loosely through the lever and clamps. Then the wiresmay be stretched to the desired tension by any suitable tensioningappliances, after which the clamps may be screwed tight. The maximumtento get them practically equal and symmetrical, then clamped andbearing screwed up until the desired tension is applied.

The spacing as well as the divergence of the wires may be varied, as forinstance, they may be clamped close together and diverge to more widelyseparated points for passage through the lever, as set forth in my saidprior application, and they may be otherwise varied within wide limits,provided only, that they be spaced apart so as to afford spaced apartplanes of opposition to the'thrust of the ball bearings which shouldtake effect in a plane between them inorder to produce the desiredcondition of stable resilient stresses.

Dust, dirt and rust producing moisture may be excluded, and thesmoothness of the bearing surfaces preserved by employing a thin layerof soft felt 34, surrounding the balls and throu h whichthe ballsproject, as indicated in *ig. 3. I find that in practic'e, this may beconveniently accomplished by assembling the parts with an unperforatedpad between the balls and the lever, the great pressure exerted bysubsequent tightening of the wires being sufficient to crush the fibersof the felt out from between the bearing surfaces. When thus arranged,the felt fibers extend into intimate relation with thebearing points andafford an efficient and convenient means for conveying theretolubricating oil which I preferably employ as an agent for perfecting thesmoothness and noiselessness of the pivotal movement.

From one viewpoint, the preferred embodiment of my present invention maybe considered as involving the use of the highly tensioned wires of mysaid prior application, Serial No. 236,735, in combination with a solidphysical means for determining the pivotal axis and as a substitute forthe noisy, imperfectly acting springs, etc, which have been employedheretofore in phonographic apparatus, in the vain attempt to preventjumping, 'rubbing and shifting of the pivotal bearing surfaces of thelever. The wires employed by me when stretched to sufficiently hightension, eliminate all noises due to the imperfect or rubbing contact ofthe bearing surfaces and they introduce no noises of their own becausethe free portions thereof are of'such small mass and of such hightension that any natural frequency vibrations which may be set up inthem are of very small total energy and are of too high frequency andtoo musical in quality to be observable among the wave forms transmittedtherethrough either in"-recording or reproducing.-

Furthermore, my physical bearing and stretched wire combination isremarkably effective in eliminating needle noises which are so oftendisagreeably prominent in reproduction of sounds from ordinary records.There is some reason tobelieve that the relatively massive proportionsof the partof the lever arm utilized for sustaining the thrust of thebearing and the stress of the stretched wires, in combination withextreme lightness of the remainder of the lever arm contribute to someextent to the decrease and practical elimination of needle noises. j

The instrumentbeing substantially free from needle, bearing, spring andother disturbing noises, damping, which is commonly needle noises andwithout any internally originated noises or notes, all of the moredelicate overtones traced in the record not observably reproduced by anyphonograph apparatus now on the market and it doesthis in louder volumeand without the needle noises and without adding any internallygenerated noises or notes of its own. This superiority holds even whenthe tension of the wires is decreased very far below the safe limit-oftensile strength of the wire. I

For the resilient tension members, I prefer to use wire approximatelylike No. 6 piano wire which is fine quality steel wire about .011 to.012 inch in diameter, but the material and size of the wire may bevaried within wide limits and I have at different times and 'withvarious objects in view used fine'r wires and alsolarger wires up to .02and even 0.34 inch in diameter. It is obvisection need not be circular.

I claim:

1. In an apparatus of the class described,

a lever, means for. pivotally vibrating said lever, a suitable support,and meansfor piva lever, means for pivotally vibrating said lever, asuitable support and pivotal bearings, one of which is a steel ballbearing, in combination with highly tensioned wires secured to thesupport, engaging said lever adjacent said ball bearing and extending indirections adapted to stress said lever against said ball bearing and toafford balanced stresses adapted to prevent lateral skewing of the leverupon said bearing, and

adjustable means for forcing said bearing against said lever to vary thetension of the wires or the position of the pivotal axis.

3. In an apparatus of the class described, a lever, means'for pivotallyvibrating said lever, a suitable support and bearings, one

of which comprises alined steel balls having pivotal contact with thelever on a line at right angles to the plane of its pivotal movement, incombination with highly tensioned wires secured to the support andengaging said lever symmetrically with respect to the pivotal line andextending in directions adapted to stress the pivotal bearing surfacesinto continuous non-slip engagement. I 4. In an apparatus of the classdescribed, a lever, means for pivotally vibrating said lever, a suitablesupport and bearings, one of which comprises a pair. of alined steelballs having pivotal contact with the lever on a line at right angles tothe plane of its pivotal movement, in combination with highly tensionedwires secured to the support, engaging said lever adjacentsaid line ofpivotal contact and extending in directions adapted to stress thepivotal bearing surfaces into continuous non-slip engagement and toafford balanced stresses in other directions adapted to prevent skewingof the lever upon said balls.

-5. In an apparatus of the class described, a lever, means for pivotallyvibrating said lever, a suitable support,- a solid bearing havingpivotal contact with the lever at spaced apart points on a line at rightangles to the plane of its pivotal movement, in combination with highlytensioned wires secured to said support and engaging said leversymmetrically with respect to the line of pivotal contact andextendingin directions adapted to stress said lever against said bearing.

6. In an apparatus of the class described, a lever, means for. pivotallyvibrating said lever, a suitable support, a solid bearing havingpivotal'contact with the lever on a line at right angles to its plane ofmovement, in combination with highly tensioned wires secured to saidsupport and engaging said lever adjacent said line of pivotal contactand extending in directions adapted to stress said lever against saidbearing and to afford balanced lateral stresses adapted to preventskewing of the lever upon the bearing.

7. A sound box having a diaphragm, a lever secured to the diaphragm,bearings on the box and on the lever contacting with each other on aline parallel with the diaphragm, in combination with wires secured tothe sound box and engaging the lever from different directions such aswill afford tension stresses cooperating to press the lever bearingdownward upon the box bearing, but mutually opposed and approximatelybalanced in other directions, and adjustable means for moving said boxbearing and lev'er substantially against the downward pressure toincrease the tension .of the wires substantially equally.

8. A sound box havinga diaphragm, a lever secured to the diaphragm,bearings on the box and on the lever contacting with each other on aline parallel with the diaphragm, in combination with resilient tensionmembers secured to the sound box and engaging the lever from differentdirections such as will afford tension stresses cooperating to press thelever bearing downward upon the box bearing, but mutually opposed andapproximately balanced -in other directions, and adjustable means formoving said box bearing and lever substantially against the downwardpressure to increase the tension of the resilient tension memberssubstantially equally. 4

9. A sound box having a diaphragm, a lever secured to the diaphragm,bearings on the box and on the lever having contact on a line parallelwith the diaphragm, in combination with a plurality of steel wirerigidly clamped to the sound box and engaging the lever, arranged toafford mutually opposing tension stresses having a resultant pressuretransversely of the lever and means operating to force the leversubstantially in the direction of said pressure, thereby varying thetensions of mutually opposing wires substantially equallv,

10. A. sound bbx,'a diaphgram, a radially extending lever secured'to thediaphragm. and pivotally mounted on the box ,--the pivotal meansincluding spaced clamps mounted on the sound box in symmetricalrelation,on'

opposite sides of the lever, steel wires stretched'between the clampsandthe lever and engaging the lever at. symmetrically spaced points onopposite sides of the lever and on opposite sides of its pivotal axis,the free portions of the wires between the clamps and the lever beingarranged diagonally to' substantially equally.

11. A sound box, a diaphragm, a radially extending lever secured to thediaphragm and pivotally mounted on the box, the pivotal means includingspaced clamps mounted on the sound box in symmetrical relation, onopposite sides of the lever, steel wires stretched between the clampsand the lever and engaging the lever at symmetrically spaced points onopposite sides of the lever and on opposite sides of its pivotal axis,the free portions of the wires between the clamps and the lever beingarranged diagonally to stay said lever against lateral and endwisemovement, in combination with means for applying a transverse thrustuponthe lever in a direction perpendicular to the plane of engagement ofsaid wires with the lever and in a plane passing between them.

12. A sound box, a diaphragm, a radially extending lever secured to thediaphragm and pivotally mounted on the box, the p1votal means includingspaced clamps mounted on the sound box in symmetrical relation, onopposite sides of the lever, steel wires stretched between the clampsand the lever and engaging the lever at symmetrically spaced points onopposite sides of the lever and on opposite sides of its pivotal axis,the free portions of the wires between the clamps and the lever beingarranged diagonally to stay said lever against lateral and endwisemovement, in combination with a bearing adapted to .contact with thelever on a line parallel with its pivotal axis and to apply a thrust atright angles to. the plane of the spaced points of engagement of thewires with: the lever and passing midway between said points.

13. In an apparatus of the class described, a lever, means for pivotallyvibrating said lever, a suitable support, a pair of alined balls mountedon said support and having pivotal contact with the lever on a line atright angles to the plane of its movement, and resilient devices forforcing said lever downward upon said balls, and means for spacing theballs consisting of V-shaped depressions formed in the surface whichsupports them. I

14. In an apparatus of the class described, a lever, means for pivotallyvibrating said lever, a suitable support, a pair of alinedballs mountedon said support and having pivotal contact with the lever on a line atright angles to the plane of its movement, and resilient devices forforcing said lever downward upon said balls, and means for spacing theballs and permitting pivotal rolling thereof, said means consisting ofV-shaped grooves formed in the ball support parallel with the lever andat .right angles to its pivotal axis.

15, In an apparatus of the class described, a lever, means for pivotallyvibrating said --lever, a suitable support, a pair of alined ballsmounted 011 said support and having pivotal contact with the lever on aline at rlght angles to the plane of its movement,

and resilient devices for forcing said lever downward upon said balls,the bearing surface of said lever being formed as a groove extendingtransversely of the lever, formed on straight line elements at rightangles to the lever and curved lengthwise of the lever whereby pressureof the resilient devices tends automatically to set the lever at rightangles to the balls.

'16. In an apparatus of the class described, a lever, means forpivotally vibrating said lever, a suitable support, a pair of alinedballs mounted on said support and having pivotal contact with the leveron a line at right angles to the plane of its movement, and resilientdevices for forcing said lever clownward upon said balls, the bearingsurface of said lever being formed as a groove extends automatically toset the lever at right angles to the balls, and means for spacing theballs and permitting pivotal rolling thereof, said means consisting ofV-shaped grooves formed in the ball support parallel with the lever andat right angles to its pivotal axis.

17. In an apparatus of the class described, a lever, means for pivotallyvibrating said lever, a suitable support, a pair of alined balls mountedon said support and having pivotal contact with the lever on a line atright angles to the plane of its movement, and resilient devices forforcing said lever downward upon said balls, and means for lubricatingthe bearing surfaces, said means consisting of a felt pad inclosing theballs between the lever and ball support.

18. In an apparatus of the class described, a lever, means for pivotallyvibrating said lever, a suitable support, a pair of alined balls mountedon said support and having ELWOOD GRI SSINGER.

